Contact device for interrupters.



ITNESSES:

A. POLLAK. CONTACT DEVICE FOR I'NT ERRU PTERS APPLICATION -FILED M AR. 1's. I913.

INVENTOR f By Aztm'ne s, I MM M QM M A. POLLAK.

CONTACT DEVICE FOR INIERRUPTERS. APPLICATION FILED MAR. 18. 1913.

L1@&,1. Patented Dec. 1915.

ZSHEETS- 2.

LNVENTOR WITNESSES:

By Attorneys, V7

15 formation of aise.)

To allwhom it may concern:

-Be it known that I, Aivron PoLLAK, a subject of the King of Hungary, residing in Paris, France, .have invented certain new 5 and useful Improvements in Contact Devices for. Interrupters, ofwh-ich the follow-- ing is a specification. I

The invention relates'to electric interrupters in which the two contactsare arranged 1 one facing the other in the ordinary manner.

- In this sort of interrupters, which are especially employed in-the \Vagner hammer, it frequently happens that the contacts very rapidly deteriorate in consequence of the 'rtor ridges, which after a certain time resist the passage of the current. This deterioration occurs very rap.- idly in interrupters of the sort named on account of the high frequency of the interrup- 20 tion spark which passes between the two contacts. If the contacts are of metal,-then at that point where the first-spark has leaped across the next spark alsoseeks-to pass in consequence of the elevation of temperature 25 produced by the first spark. The result thereof is that the contacts are. eaten away at tlllSPOlIlt; If the contacts, on' the other hand, are carbon then. there isdt'ormedat this point a ridge which gradually increases and so finally extends across the space between the .two contacts;

. For avoiding-injurious phenomena of the character above mentioned it has been proposed that interrupters be constructed to at in'rpart toioneor both contacts, besides the ordinary movement" for interrupting the current, a second movement, producing a relative shifting of the contact: surfaces and causing. friction at suchsurfaces. It has to, been-proposed .for example to 'arrangethe contact onasheetzspring, which on the occa.-'

sion of shock or other influences causes oscillation of the contacts'perpendicularly to the movement of interruption.-

lite 5 Th'e-object of the present invention is to assure underallcircumstancesthe most perfoot working of this kind of interrupters.

In accordance with the invention thecontact executing. the secondary "movement is. at-

tth tached to a, system of several sprin' s, whereby the important iadditional technical eflect is obtained, :thatnot onlykthe eflect of'th'e vibration :itself islincreased but that ialliicirclnnstances the simultaneousmovett t, f tvgo on; several spriiigs-e-assures-ia' strictly parallel displacement, and this with conrracr nnvrcn non iu'rnn nnr'riins.

is produced between thetwfdsurfaces ti? i Specification of Letters Patent. Patented lllteqc aid, A plication filledMarch18,1913.- seriaino.'755,o94.' Y i1 asingle spring "(especially if thesame, as in the well known devices isslackened against the contact, that is, against the free loaded the most effective manner, the continued change of the contact points from time to time, in accordancewith the invention the period of vibration of the displacement 70 movement is chosenIlonger than that of the interruption movement, in order to surely effect a relative movement of the twopoints between which the. previous interruption took place. I 5 The drawings illustrate the invention in several embodiments byway of examples.

Figures 1,2 and 3 are side elevations'of threedifierent arrangements embodying the invention insimple forms. Fig? 2 is a my plan view of the mechanism shown in Fig. 2. Fig. 4 is a vertical. section of an arrangement for producing .a' rotary movement.

'Fig. =5 is an elevationofthe'same. .Fig.

6 is. a horizontal section of another arrangeat ment for producing a rotary movement, and Fig." 7 an elevation of the same, partly 1n section. I

The construction shown in Fig. 1 is suitable-for cases'where the interrupter issu'san pended in such a way that it is'exposed to external vibration, for example when'i-t is arranged on a dynamo, a motor, or a'power vehicle; or, when the int'errupters are closed with a shock suflicient toset in vibration a at spring acting on one of the contacts. The

' contact A has the form of a hammer, which the two contacts is set into Evibration, then the contact B will moveback and. forth parallel to the contact surface, whereby thgre sired displacement-mud {*friction. weight increases the .efiectg If the contact B is itself heavy enough, then the use of a special weight D is superfiuous. I

The construction illustrated in Figs. 2

and 2* is also adapted for interrupters which are exposed to external shock. rangement the contact B is fixed. Of the two pivot pins a on opposite sides of the contact A, the one which lies behind the orsurface of the paper is supported in the ordinary manner, whereas the one lying to the front is supported on a yoke b'which forms one arm of a bell-crank E, which at the end ofthe other arm carries a weight F,

which is 'held by a spring f. The weight F swings under the action of the external shocks and thereby causes the lever E to swing with it which by means of the yoke imparts to the contact A slight displace: 2 ments in a plane which is parallel to that of the contact surfaces. There will therefore take place between these surfaces a slight friction which "is sufficient to attain the end in view. I

The arrangement according to Fig. 3, is, in contradistinction to those previously described, employed ifzthe contacts are not exposed to sufficient external vibration. In all the figures the contact A is that which is moved in the interrupting operation and the contact B the one which is at rest. To permit displacement of the contact B (in Fig. 3) in a direction parallel to the contact surfaces, it is supported by two or several leaf springs C which permit vibration in the desired direction. Moreover it is provided with an armature of soft iron G which can be moved by a special electromagnet which is traversed by any variable or intermittent current whatever. In the construction illustrated, however, the electromagnet which produces the displacements of the contact A itself'is used to impart the desired blow or movement to the armature G. For this purpose the electromagnet I,

causing the change of position of the contact A is provided with a prolongation a' which acts upon the soft iron armature G towhich the contact B is fastened.

- In all the above described devices the interrupting mechanism and the lateral displacement mechanism may have different periods of oscillation, and the amplitude of the two movements can be chosen in such manner that it is most favorable for producing the parallel displacement and the friction in the desired manner, the dura-" 'tion of vibration of displacement movement is preferably chosen longer than the move ment of interruption, whereby the contact will be surely held in the regulation condition, and the interruption of the current becomes more rapid. a

The contactB may" also be arranged to es produce'the parallel displacements through In this ar-' a rotation or oscillation about its longitudinal a'xis, this rotation or vibration being producedby means of any desired device. Especially in the case where strong currents areto be? constantly interrupted-and the amplitude of the back and forth swing is not great, it appears advisable to impart to one of the co'ntacts together with vibrating movement, a constant, even if slow, rotation in order that those points between which the current has just passed and become interrupted shall be thereafter removed from. each other locally. In this mode of operation the two contact surfaces remainperfectly smooth and uniform, even in cases of an overload which might produce craters on the surfaces under a strain or overloadcontinued for a comparatively long time in the vibratory devices above described. The vibratory movements above described may be utilized at the same time for imparting to the contact the desired rotation. For this purpose the contact may be connectedwith a ratchet wheel which engages a stationary pawl and is thereby rotated. 1

The contact B (Fig. 4) is set into the frame 1 which carries a ratchet wheel 2. The frame 1 has internal longitudinal grooves 4 and 5 which receive similar projections 6 and 7 on the contact B. The pressure spring 3 and the pin 8 determine the position of the contact B in the direction toward and from the interrupter contact A. By means of the set screw 9 the contact B can be set up. The frame 1 is rotatably arranged in the body. 10 which is carried by the two springs 11 and 12 (Fig. 5) so that this body 10 on vibrations or influences of the above-described kind oscillates in the direction of the arrow. At each oscillation the ratchet wheel 2 is pushed against the pawl 13, which may consist of a small spring, whereby the ratchet wheel is rotated forward one or more teeth. There arises thereby a progressive rotation of the contact B.- The set screw 9 remains stationary while the metal pin 8 lying in the two hollows 14, 15, allows the free swinging of the body 10, and at the same time serves for the conducting of the current. If the contact B is of carbon, then it is Provided with a metal cap 16 at the point of engagement with the metal pin 8.

In the construction shown in Figs. 6 and 7 there is effected, in addition to a vibration and a continuous rotation, an automatic setting up of the contact B as it wears away. This device difi'ers from the one described in connection with Figs. 4 and 5, first in the fact that the set screw 9 and metal pin 8 are lacking. The ratchet wheel 2 is held fast in the body 10 by means, of the spring 21 which for the purpose of permitting removal of the ratchet .wheel is rotatable relatively to the frame and contact B. Further, the frame 1 is open at thefront and the body 10 is provided with lugs 22, 22 against which the pressure spring3 presses the contact B.

Pins 23 serve to carry the contact B with the rotating ratchet wheel. The contact A has in this case an oblong cross-section and a similar contact face, so that the" latter is longer than the diameter ofthe contact B. Contact B (the positive pole) at the point of engagement with the contact A is slowly used up. In consequence of the rotation of the contact B all the points of the same pass over the contact face of A gradually, whereby in consequence of the pressure of the spring 3 the front surface of the contact B is held automatically and constantly against the lugs 22, 22, so that its working contact surface remains unchanged as regards the contact A.

The contact B in both the embodiments.

illustrated in Figs. 4-7, is perforated in the middle because in the middle portion the effect aimed at by the rotation would not occur. I

I claim as my invention 1. A contact device for interrupters including a pair of contacts, one of which is movable toward and away from the other, and a system of springs for supporting one of said contacts, said springs being yieldable transversely of the contact movement of said contacts and rigid. in the line of such move ment whereby a secondary movement of the contacts will be aflordcd in a direction parallel with the contact surface, and means for rotating one of said contacts relatively to the other.

2. A contact device: for interrupters including a pair of contacts one of which is movable toward and away from the other,

and a'spring support for the other adapted,

other contact, a'ratche't Wheel connected to the said contact carrying means, and a sta tionary pawl for engaging the ratchet wheel.

4. A contact device for interrupter-s including a pair of contacts one of which is movable toward and from the other, a system of springs yieldable transversely of the contact movement of said contacts and rigid.

in the line of such movement, carrying mean simountc'd on said springs for said other contact, a ratchet wheel connected to the said contact carrying means, and a stationary pawl. for engaging the ratchet wheel, said carrier being provided with lugs for positioning the contact face of the contact carried thereby, and a spring for pressing said contact against the lugs.

In witness whereof, I have hereunto signed my name in the presence of two subscribing witnesses.

ANTON POLLAK.

Witnesses:

THoMAs vf vv ALLAGE, FRED WHITE. 

